Improvement Of The SPIHT Algorithm For Hardware Implementation

With the development of the remote sensing technology and the increase of the spatial resolution, satellites of remote sensing have been widely used in the national economy and the national defense. Although we have obtained much information by processing lots of data, more need to be processed. As a result, the On-board System is enduring a great difficulty on storage and transmission remote sensing image, and this problem can not be solved well by only increasing the ability of the storage and transmission. In this situation, it is important to find a high-speed image compression algorithm which is proper for the characteristics of remote sensing image, and to optimize it basing on specific hardware.The embedded image compression based on the wavelet transform belongs to the image coding techniques which are widely studied in recent years, and its characteristics which include higher-compression-rate, embedded bit-stream, lower computer complexity, satisfy most the requirements in the compression of remote sensing image. In this thesis, we mainly study this kind of image coding technique, and then choose the Set Partition in Hierarchical Trees (SPIHT) to perform the improvement on. The improvement is achieved by taking into account the characteristics of the remote sensing image, the compression algorithms, and the hardware systems. From four aspects, including wavelet transform, processing pattern, error resilient, and optimization of DSP code, we improved SPIHT algorithm and obtained some achievement as bellow:1. Replace the convolution by the integer wavelet lifting, and the calculation of wavelet transform becomes easy to be implemented in hardware.